Qingre-Qushi Recipe (QRQS) ameliorated atopic skin inflammation in Th17-dominated mice via regulating the STAT3/STAT5 pathway

Flaky tail mice, a spontaneous Th17-dominated AD-model, were treated with different concentrations of QRQS and Cetirizine. The dermatitis score and scratching frequency were evaluated, and histological evaluation was performed according to a standard protocol. Changes in the T-helper cell population were analysed by flow cytometry. The serum levels of IgE and IgG1 were determined by ELISAs. The levels of T helper (Th) cell associated cytokines in serum and skin lesions were determined by ELISAs and RT-PCR. STAT5 and STAT3 were assessed by Immunoblotting.<br> QRQS ameliorated AD-like symptoms and decreased dermatitis scores and scratching frequencies. The middle dose of QRQS had the optimal effect, we study the potential mechanism based on this. After QRQS treatment, the imbalance of Th17/Treg was corrected. In addition. inhibited STAT5 was activated, and the associated cytokines were up-regulated. STAT3 overexpression was reversed, and the associated cytokines were downregulated. Moreover, the expression of Th2 cytokines was suppressed, and Th1 cytokines were overexpressed which may be attributed to changes in the STAT5 and STAT3 pathways <br>